88 Headlight Motors (Page 1/1)
OldGuyinaGT MAR 07, 07:04 PM
My left side headlight motor failed (symptoms of broken torque pins). I bought rebuild kits from The Fiero Store two years ago, anticipating that the motors would someday go, since the left side was a little balky for a while. I also had a spare set of complete 88 headlight mechanisms, with motors. I tore down both of my left motors. The one off the car had gear tooth damage; the yard one had busted torque pins. I also broke one of the motor screws on the one off the car (would appreciate tips on how to get that out. I already tried drilling it and the bit walked off the screw and put a nice dimple on the housing)

When I went to rebuild the yard one, I had several problems. The hub (for lack of a better term) on the output shaft of the motor wouldn't fit inside the new gear. I put it on a miniature lathe and turned the major diameter down until it fit - probably -0.04" or so diameter. Then I tried to reassemble it and found that the new torque pins were too large. I finally put together a combination of parts - turned output shaft hub, unbroken torque pins from the original motor, new gear - that would fit (torque pins are tight), and reassembled the motor. I used the same shims that came out, in the same positions, but I don't know if that's correct for the new gear (how much end play should there be? Seems like there's a lot) Turning the knob moves the headlight assembly like it's supposed to.

I put it in the car and turned the knob to put the headlight in the full down position. But I noticed that it didn't stop when the headlight was full down. I tested with power and the motor raises and lowers the headlight with the hood up, but runs for 3-4 more seconds after reaching either end of travel, and won't move with the hood down (can't move the headlight doors. This is what it did before I started working on it. I've torn the motor back down twice since but can't find the problem. The gear teeth don't show damage from running on at the end of travel. I can't turn the output shaft with a much force as I'm willing to put on it. What am I missing here?

I just ordered a pair of new Cardone motors. But I'd like to make these usable. Has anyone else had this problem?

theogre MAR 07, 09:24 PM
Normally... Motor runs @ EoT and everything "Looks Fine" likely means output shaft has failed.
Module kills power after ~ 5 sec even when motors are disconnected electrically or mechanically from rest of lift assem. IOW like you unplug a motor or link is broken near motor, pin failed, etc, and motor try to run forever.

See my Cave, Gen 2 HL Motor
http://www.fiero.nl/forum/F...HTML/128600.html#p37

Hard Delrin pins are known for problems but even replacing OE pins w/ same can still "break" the gear or shaft if they have problems too.
TFS may sell relabeled Dorman 74410 and if true doesn't fit most Gen2 HL motors w/o cutting down them to fit.

But you also had to make the gear to fit the output shaft is problem of its own...
whatever gear doesn't fit the output is wrong for the unit and maybe doesn't engage the motor shaft right too.
Example: If someone replace OE gear w/ repop "plastic" gear... many were made wrong and shrink over time.

"Shims" are part of the output shaft bearings. They and plastic gear and large brass part makeup a thrust bearing because gearing is Worm type that puts axial loads on the output shaft. Make sure has a least 1 shim on each side of gear.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

OldGuyinaGT MAR 08, 01:23 AM
I would have hoped that Fiero Store parts wouldn't have shrunk that far, but the possibility did occur to me since neither the output shaft nor the pins fit without alteration. I would hope they weren't just plain wrong, considering the source.

I'm going to take one more shot at it, with the original gear that at least looks okay, and the original pins from the other motor that were intact. If that works I'll at least get one good motor out of the two. If not, is there another source for gears/pins other than Rodney's aluminum one? If not I may go with those just so what I have here can be more than paperweights...